package com.fasterxml.jackson.datatype.guava;

import com.fasterxml.jackson.core.Version;

import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.datatype.guava.ser.GuavaBeanSerializerModifier;
import com.google.common.collect.BoundType;

import static com.google.common.base.Preconditions.checkNotNull;

Basic Jackson Module that adds support for Guava types. 

Current configurability includes:

configureAbsentsAsNulls (default: false):
   Determines whether inclusion strategy of NON_NULL should additionally consider
   Optional.absent() values (as POJO properties) to be excluded; if true, they will
    be excluded, if false, they will be included.
    Note that the defaults for other "Optional" types are different; Guava setting is chosen solely
    for backwards compatibility.
 

/**
 * Basic Jackson {@link Module} that adds support for Guava types.
 *<p>
 * Current configurability includes:
 *<ul>
 * <li><code>configureAbsentsAsNulls</code> (default: <code>false</code>):
 *    Determines whether inclusion strategy of <code>NON_NULL</code> should additionally consider
 *    <code>Optional.absent()</code> values (as POJO properties) to be excluded; if true, they will
 *     be excluded, if false, they will be included.
 *     Note that the defaults for other "Optional" types are different; Guava setting is chosen solely
 *     for backwards compatibility.
 *  </li>
 *</ul>
 */
public class GuavaModule extends com.fasterxml.jackson.databind.Module // can't use just SimpleModule, due to generic types
{
    private final String NAME = "GuavaModule";

    
Configuration setting that determines whether `Optional.absent()` is
considered "same as null" for serialization purposes; that is, to be
filtered same as nulls are.
If enabled, absent values are treated like nulls; if disabled, they are not.
In either case, absent values are always considered "empty".

Default value is `true` for backwards compatibility (2.5 and prior
only had this behavior).

Note that this setting MUST be changed BEFORE registering the module:
changes after registration will have no effect.
/**
     * Configuration setting that determines whether `Optional.absent()` is
     * considered "same as null" for serialization purposes; that is, to be
     * filtered same as nulls are.
     * If enabled, absent values are treated like nulls; if disabled, they are not.
     * In either case, absent values are always considered "empty".
     *<p>
     * Default value is `true` for backwards compatibility (2.5 and prior
     * only had this behavior).
     *<p>
     * Note that this setting MUST be changed BEFORE registering the module:
     * changes after registration will have no effect.
     */
    protected boolean _cfgHandleAbsentAsNull = true;
    protected BoundType _defaultBoundType;
    
    public GuavaModule() {
        super();
    }

    @Override public String getModuleName() { return NAME; }
    @Override public Version version() { return PackageVersion.VERSION; }
    
    @Override
    public void setupModule(SetupContext context)
    {
        context.addDeserializers(new GuavaDeserializers(_defaultBoundType));
        context.addSerializers(new GuavaSerializers());
        context.addTypeModifier(new GuavaTypeModifier());

        // 28-Apr-2015, tatu: Allow disabling "treat Optional.absent() like Java nulls"
        if (_cfgHandleAbsentAsNull) {
            context.addBeanSerializerModifier(new GuavaBeanSerializerModifier());
        }
    }

    
Configuration method that may be used to change configuration setting
_cfgHandleAbsentAsNull: enabling means that `Optional.absent()` values
are handled like Java nulls (wrt filtering on serialization); disabling that
they are only treated as "empty" values, but not like native Java nulls.
Recommended setting for this value is `false`, for compatibility with other
"optional" values (like JDK 8 optionals); but the default is `true` for
backwards compatibility.
Returns:
This module instance, useful for chaining calls
Since:
2.6/**
     * Configuration method that may be used to change configuration setting
     * <code>_cfgHandleAbsentAsNull</code>: enabling means that `Optional.absent()` values
     * are handled like Java nulls (wrt filtering on serialization); disabling that
     * they are only treated as "empty" values, but not like native Java nulls.
     * Recommended setting for this value is `false`, for compatibility with other
     * "optional" values (like JDK 8 optionals); but the default is `true` for
     * backwards compatibility.
     * 
     * @return This module instance, useful for chaining calls
     * 
     * @since 2.6
     */
    public GuavaModule configureAbsentsAsNulls(boolean state) {
        _cfgHandleAbsentAsNull = state;
        return this;
    }

    
Configuration method that may be used to change the BoundType to be used when deserializing Range objects. This configuration will is used when the object to be deserialized has no bound type attribute. The default BoundType is CLOSED. 
Params:
boundType – BoundType
Returns:
This module instance, useful for chaining calls
Since:
2.7/**
     * Configuration method that may be used to change the {@link BoundType} to be used
     * when deserializing {@link com.google.common.collect.Range} objects. This configuration
     * will is used when the object to be deserialized has no bound type attribute.
     * The default {@link BoundType} is CLOSED.
     *
     * @param boundType {@link BoundType}
     *
     * @return This module instance, useful for chaining calls
     
     * @since 2.7
     */
    public GuavaModule defaultBoundType(BoundType boundType) {
        checkNotNull(boundType);
        _defaultBoundType = boundType;
        return this;
    }
    
    @Override
    public int hashCode() {
        return NAME.hashCode();
    }

    @Override
    public boolean equals(Object o) {
        return this == o;
    }
}